Mistakes are bound to happen, but whether you make a minor glitch or a major mess-up, how you react (beyond the choice words that run through your head) matters much more than what you did.
Admit Your Mistake
As soon as you discover that something went awry, immediately tell your boss. The only exception is, of course, if you make an insignificant error that will not affect anyone or if you can fix it before it does. Otherwise, don't try to hide your mistake. Doing that will make you look a lot worse if someone else discovers it and you could be accused of a coverup. Being upfront about it will demonstrate professionalism, a trait most employers greatly value.
Show you’re in control of the problem
When disclosing the mistakes you’re making at work, have a few suggestions as to how you plan to fix the problem. Offer the best solution first to make the situation seem less dire. Show you’re in control. You’ve already learned from your mistake, and you’re already working to fix things. It doesn’t mean you’re not going to get yelled at, but it might mean your boss will take note of your character throughout the situation. Handle this well, and minimize the damage, and you might maximize your boss’s good opinion.
Turn your mistakes into a learning experience
Seriously, everybody screws up every now and then. Don’t beat yourself up too hard. For one thing, it’s a waste of time. For another, if you’re too busy gnashing your teeth, you won’t have time to learn from your mistake. So turn this failure into a life lesson, and use it to help make you better at your job. Use it to help you grow. Debrief yourself, alter your course to avoid similar fudge-ups in the future, and then move forward.
Earn Your Boss’ Trust Back
Even if you did all of the above, you’ll still have to earn back trust. Start small—get all your smaller projects off your desk, with efficiency and precision. Log these minor victories in quick succession. Then move on to bigger ones. Go the extra mile as often as you can. Little by little, your boss will be so charmed that he’ll forget what happened last month—he’ll be too busy reveling in the quality of your work this month.
You’re going to mess up eventually. What matters isn’t when or how, but how you choose to handle yourself in such situations. When in doubt, choose honesty, integrity, and good hard work to pull things back together.